Induced *-representations and $C^{\ast }$-envelopes of some quantum $\ast$-algebras

Abstract

We consider three quantum algebras: the q-oscillator algebra, the Podles' sphere and the q-deformed enveloping algebra of $su(2).$ To each of these *-algebras we associate certain partial dynamical system and perform the "Mackey analysis" of *-representations developed in [SS]. As a result we get the description of "standard" irreducible *-representations. Further, for each of these examples we show the existence of a "$C^{\ast }$-envelope" which is canonically isomorphic to the covariance $C^{\ast }$-algebra of the partial dynamical system. Finally, for the q-oscillator algebra and the q-deformed $\cU(su(2))$ we show the existence of "bad" representations.